Internal combustion engine



April 4, 1933. H. 1-. A DORNER 1 903,316

INTERNAL COMBUSTION ENGINE Filed Nov. 151 193].

HERMHNN 1 11 Emma.

Patented Apr. 4, 1933 UNITED STATES PATENT ol-"Fica HEB/MANN I. A. DOBNER, OF HANOVER, GERMANY, ASSIGNOR 1'0 PACKARD MOTOR CAB COMPANY, 01 DETROIT, MIQHIGAN, A CORPORATION OF MICHIGAN INTERNAL COMBUSTION ENGINE Application filed November 19, 1881. Serial No. 576,122.

This invention relates to internal combustion engines and more particularly to means for controlling the flow of charges of air into engine cylinders.

As pointed out in my Reissue Patent No. 17,775, of August 19, 1931, it is important that engines of'the Diesel type, in which 'fuel is injected into highly compressed air in the cylinders, that the air must be controlled in its movement in order to obtain the necessary commingling with the fuel.

It is an object of this invention to improve the form and arrangement of the air inlet passage in an engine, of the type shown in my above mentioned patent, so that air will pass into the cylinders without any interference from the valve heads.

Another object ofrmy invention is to increase the efliciency of an internal combustion engine, of the Diesel type in which air and fuel are introduced separately into and mixed in the cylinder, through the introduction of an air stream in a manner such that the controlling valve interrupts the air flo to a minimum extent. r

A further object of my invention is to introduce an air charge into a cylinder in an uninterrupted path between a valve head, opened a relatively short distance, and the end wall of the cylinder with which the 'valve is associated.

Other objects of the invention will appear from the following description taken in connection with the drawing, which forms a part of this specification, and in which:

Fig. 1 is a plan view of an engine cylinder with which my invention is shown incorporated.

Fig. 2 is a vertical section view of the upper'part of a cylinder showing the air inlet passage and the associated valve mechamsm.

Fig. 3 is another sectional view taken on line 3-3 of Fig. 2, illustrating the form which the air inlet passage takes at its throat.

Referring now to the drawing by characters of reference, 10 indicates a cylinder of an internal combustion engine, ofthe four stroke Diesel type, having an integral dome or end wall 11 and a plurality of coolis a bushing 17, through which the valve stem 18 extends, such stem terminating in a valve housa head 19 within the cylinder. The valve is normally maintained in closed position by a plurality of coiled springs 20, which are seated in recesses in the housing and engage against the plate 21 fixed to the outer end of the valve stem. Within the housin a rock lever 22 is pivotally mounted on a s aft 23 and carries a roller 24: at one end for'engagement with the end of the valve stem. The other end of the lever 22 overhangs the cylinder, and suitable engine operated push rod mechanism (not shown) is associated therewith to open the valve.

The engine illustrated is of the four cycle type. The valve is held open during the exhaust stroke, the intake stroke and part of the compression stroke. The valve is closed during part of the compression stroke and during the power stroke, and a suitable oil injection device, as indicated at 27, delivers atomized fuel charges into'the compressed air vcharges during the last part of the compression stroke.

Extending through the head and the dome "I his combined air inlet and exhaust outlet passage is arranged so that-it extends at an oblique angle to the cylinder axis and tangential to the cylinder, and also with its junction with the cylinder eccentric to the axis of the dome. By means of this arrangement of the passage, air will be drawn into the cylinder in a stream and at a high velocity during the suction stroke of the piston 41, and such stream after striking the cylinder wall, will be deflected so that it moves in a rotary direction which continues during the compression stroke until combustion takes place. As considerable air must be drawn into the cylinder in a comparatively short time, I make the passage so that it is in the form of a venturi.

When the passage 40 is circular in cross section, as shown in my previously mentioned patent, the distance the valve head must move to open position in order to prevent its interfering with theincoming stream of air before striking the cylinder, depends upon the diameter and angle of the passage. In some instances such a valve opening limits the piston movement so that a desired compression ratio cannot be obtained, and consequently, the compression ratio must be lower than desired or the valve opening must be lessened to an extent such that its head deflects a portion of the incoming air.

uniform width throughout its length. The

space between the open valve head and the dome will be in a direct line with and of slightly larger dimensions than the throat of the passage so that the head will thus not interfere with the air moiement in a rectilinear stream from the passage outlet to the cylinder-wall. The valve stem traverses the center of the wider portion of the passage so that air deflection due to this cause is reduced as compared with that caused by a valve stem in a similar volume circular passage. The width of the passage is several times the height thereof and the angular relation of the passage is such that the valve head will be readily cleared by the intake stream even though it is opened a relatively small amount.

This form of air passage results in a high rotational speed of air within the cylinder because of the minimum interference with its movement while passing inwardly. With this flat passage, the valve can be opened a minimum extent without int rference with the incoming air stream and consequently a high compression ratio can be had.'- It will further be seen that the capacity of the passage is in no way diminished through .being formed and arranged as described here- Although the invention has been described in connection with a specific embodiment, the principles involved are susceptlble of numerneonate ous other aplications which will readily occur to persons skilled in the art. The invention is therefore to be limited'only as indicated by the scope of the appended claims.

What I.claim is:

1. In an internal combustion engine, a cylinder, an inwardly opening 'valve in the cylinder head, and an elliptical air inlet passage through the head controlled by said valve, said elliptical passage being of Venturi form and extending tangentially of the cylinder and obliquely to the axis of said valve.

2. In an internal combustion engine, a cylinder having an air inlet passage of Venturi form extending through the head, and a poppet valve co-operating with the inner end of the passage and having a stem extending through the cylinder head and the passage, the axis of the passage extending obliquely to thevalve axis and the passage being of a major dimension in a direction transversely of the valve axis.

3. In an internal combustion engine, a cylinder having an air inlet passage of Venturi form extending through the head, and a poppet valve extending through the cylinder head and having a head operating within the cylinder and adapted to close the inner end of the passage, said valve head being adapted to open sufficiently to provide an uninterrupted air outlet into the cylinder in alignment with and of substantially the same transverse sectional form as the throat portion of the passage.

4. In an internal combustion engine, a cylinder having an elliptical Venturi air inlet passage of substantlailly a uniform width extending through the head, and a poppet valve having its stem extending through the cylinder head and its head operating 1nteriorly of the cylinder and to close the inner end of the passage, the axis of the passage extending obliquely to the valve axis and directing an air stream from its throat into the cylinder of substantially uniform section. A

'5. In an internal combustion engine, a cylinder having a flattened air inlet' passage of Venturi form extending through the head, and an inwardly opening poppet valvehaving its stem extending through the cylinder head and adapted to close the interior end of the passage, said valve opening sufiicient- 7 1y to permit air to enter the cylinder wlthout interference throughv the space. between the valve head and the interior end of. the passage in alignment with the throat portion of the passage.

In testimony whereof 'I afix my signature. HERMANN I. A. DORNER. 

